No Such Thing As Type 2 Diabetes? Why Old Notions Of 'Disease' Need Revamping

Obesity was a status symbol in Renaissance culture: "The Tuscan General Alessandro del Borro". It is now generally regarded as a disease. (Photo credit: Wikipedia)

As medicine advances, thanks to expanding research and sophisticating technologies, it’s always got the task of shedding its past and redefining itself. Part of this is to rid itself of conventions that are determined to be useless, or worse, erroneous. In a smart new editorial in The Lancet, researcher Edwin Gale of the University of Bristol argues that there’s a major problem with the way we think about disease today, in particular the ones that are not so clear cut, like type 2 diabetes, which itself affects millions across the globe, and now includes a growing new subset: children. But slapping the “type 2 diabetes” label on a wide constellation of symptoms (and, perhaps, causes) that has no simple treatment is a major “category error,” argues Gale. And this error can lead us – researchers and patients alike – down the wrong path when it comes to solutions.

Here’s Gale’s central argument. He says that medicine, unfortunately, still has the tendency to look for a unique cause and/or symptom to define a “disease.” As it happened in the case of diabetes, over a century ago, a researcher decided that blood sugar was the way to define the disease, and this convention has, very sadly, stuck. Even today, committees of experts sitting around a table deciding what defines normal and abnormal blood sugar is considered an acceptable method. But, argues Gale, it’s not acceptable at all, and we need a better way: “a problem that cannot be defined in scientific terms cannot have a scientific solution.”

What we’ve learned in the last 50 or 60 years is that diseases like type 2 diabetes are actually multifactorial, and they’re “defined by their attributes and consequences rather than by their causal mechanisms, which remain unknown.” In the case of type 2 diabetes, after all, we don’t really know what causes it: We know that the body doesn’t use insulin correctly, and that there’s a laundry list of associated risk factors – overweight and obesity, being sedentary, high levels of blood fats, etc. – but we don’t really know what's happening in the body to lead to the condition (or group of conditions). And as numerous the causes, so can be symptoms, which often vary widely from person to person.

Therefore, Gale says, “assuming standard causal mechanisms and universal treatment pathways” is our fatal flaw, and it leads to major problems in the solutions for the “disease.” He adds that our outdated notion of type 2 diabetes has led to decades of wasted research that could have been better spent in other avenues.

As Gale told the Lancet TV, "If you give something a name, you imply an entity; you imply that this thing actually exists. In practice, when somebody like myself talks about Type 2 diabetes, I'm saying 'a form of diabetes for which I can find no other cause'. In other words, it's a diagnosis of exclusion…There are various conditions, spectrums, and severities of diseases, all wrapped into this one definition."

So what’s the solution, should “type 2 diabetes” be scribbled out of the medical texts? The answer, in a manner of speaking, is yes. Gale suggests that we have to realize that our current thinking has gotten us nowhere and to seriously readjust how we approach disease. "When a century of scientific endeavour brings us round to the conclusion that we cannot define what we are talking about, it might be time to consider adjusting our minds.”

He proposes we scrap the term “type 2 diabetes” and replace it with “idiopathic hyperglycemia,” at least for the time being. He realizes that changing our thinking will be a long process, since there’s a lot of money and power tied up in the old ways – but new thought leaders will emerge and help shift things in a better direction. “Ruling paradigms become entrenched around the sources of money and influence, and new thinking must wait for the present generation of power brokers to move into the rose garden. The ghostly entity of type 2 diabetes is likely to haunt us for years to come, although we might for the interim avoid a terminological loop by referring to it as idiopathic hyperglycaemia.”

Different disciplines have to collaborate, he says, since the “disease” is multifactorial – so should the effort be toward understanding it. “Present thinking examines glucose or lipids; future thinking will abandon the sectarian boundaries of academic specialties to achieve a more integrated view of phenotypic development. Idiopathic hyperglycaemia will no longer be considered as a disease in its own right, but as an outcome of networked processes contributing to the affluent phenotype of adiposity, hypertension, hyperglycaemia, hyperlipidaemia, and cancer.”

Science is undergoing a lot of changes and unrest right now (not that it's ever not). Definitions of mental health disorders are being called into serious question. Major organizations are at odds over recommendations for when women should begin having mammograms. And years later, we’re still living with the specter of the flawed autism-vaccine study that was formally retracted, but which many still take as gospel. Things will change, we hope, though it may be slow.

So how long does it take science to shrug off old notions and definitions? Decades, or perhaps years, if we're lucky. While researchers debate the fate of “the disease formerly known as diabetes,” please weigh in below on how science can best evolve, and how we should conceptualize these conditions that don't have a clear cause or cure.